Mathematical challenges for able pupils Year 5 E Securing number facts, relationships and calculating
Square it up You need six drinking straws each the same length. Cut two of them in half. You now have eight straws, four long and four short. You can make 2 squares from the eight straws. Arrange your eight straws to make 3 squares, all the same size. Visualise 2-D shapes.
For example: Solution to Square it up Visualise 2-D shapes.
Spot the shapes 1. How many triangles can you count? Visualise 2-D shapes. Explain methods and reasoning.
Spot the shapes 2. How many squares can you count? Visualise 2-D shapes. Explain methods and reasoning.
Spot the shapes 3. Draw your own diagram to count triangles. Don t use too many lines! How many triangles can a friend find? Can you find more? Visualise 2-D shapes. Explain methods and reasoning.
Solution for Spot the shapes 1. There are 11 triangles. 2. There are 17 squares. Visualise 2-D shapes. Explain methods and reasoning.
Three digits Imagine you have 25 beads. You have to make a three-digit number on an abacus. You must use all 25 beads for each number you make. Hundreds Tens Units How many different three-digit numbers can you make? Write them in order. Know what each digit represents. Order a set of whole numbers.
Solution to Three digits You can make six different numbers. In order, the numbers are: 799, 889, 898, 979, 988, 997.
Make five numbers Take ten cards numbered 0 to 9. Each time use all ten cards. Arrange the cards to make: Five Make numbers prime up more numbers that problems are multiples to use of of all 3. 7 ten cards to make five special numbers. Know 3 and 7 times tables. Recognise prime numbers.
Solution to make five numbers For example: a. 12, 39, 45, 60, 78. b. 7, 42, 63, 98, 105. c. 5, 23, 67, 89, 401. There are other solutions. Know 3 and 7 times tables. Recognise prime numbers.
Maze Add and subtract two-digit numbers mentally. Multiply and divide by single-digit numbers. Start with zero. Find a route from Start to End that totals 100 exactly. Which route has the highest total? Which has the lowest total? Now try some different starting numbers.
Solution to Maze problem There are two routes that total 100 exactly: + 6 x 7 6 x 3 8 = 100 + 9 x 7 3 x 5 5 = 100 The route giving the highest total is: + 9 x 7 6 x 7 8 = 391 The route giving the lowest total is: + 6 x 7 3 x 3 8 = 34 Add and subtract two-digit numbers mentally. Multiply and divide by single-digit numbers.
Jack s book The pages of Jack s book are numbered from 1. The page numbers have a total of 555 digits. How many pages has the book? How many of the digits are a 5? Know what each digit represents.
Solution to Jack s book The book has 221 pages. 42 of the digits are a 5. Know what each digit represents.
Flash Harry In April Flash Harry bought a saddle for 100. In May he sold it for 200. In June he was sorry he had sold it. So he bought it back for 300. In July he got tired of it. So he sold it for 400. Overall, did Flash Harry make or lose money? How much did he make or lose? Use negative numbers.
Solution to Flash Harry Flash Harry s bank balance looked like this. April 100 May + 100 June 200 July + 200 So Harry made 200 overall. Use negative numbers.
1. My age this year is a multiple of 8. Next year it will be a multiple of 7. How old am I? Age old problems Know multiplication facts to 10 x 10. Recognise square and cube numbers.
Age old problems 2. Last year my age was a square number. Next year it will be a cube number. How old am I? How long must I wait until my age is both a square number and a cube? Know multiplication facts to 10 x 10. Recognise square and cube numbers.
Age old problems 3. My Mum was 27 when I was born. 8 years ago she was twice as old as I shall be in 5 years time. How old am I now? Know multiplication facts to 10 x 10. Recognise square and cube numbers.
1. I am 48 years old (or possibly 104). 2. I am now 26 years old. In 38 years time, when I am 64, my age will be both a square number and a cube. 3. I am 9 years old now. Know multiplication facts to 10 x 10. Recognise square and cube numbers. Solution to age old problems
Zids and Zods Zids have 4 spots. Zods have 9 spots. Altogether some Zids and Zods have 48 spots. How many Zids are there? How many Zods? Know multiplication facts to 10 x 10. Add two-digit numbers mentally.
Zids and Zods What Sims have 5 spots and Sams have 7 spots and there are 140 spots altogether? Find as many solutions as you can. Know multiplication facts to 10 x 10. Add two-digit numbers mentally.
Solution to Zids and Zods 1. There are 3 Zids with 4 spots and 4 Zods with 9 spots. 2. If Sims have 5 spots and Sams have 7 spots, the possible ways of making 140 are: 28 Sims; 21 Sims and 5 Sams; 14 Sims and 10 Sams; 7 Sims and 15 Sams; 20 Sams. Know multiplication facts to 10 x 10. Add two-digit numbers mentally.
Franco s fast food This is what food costs at Franco s café. 1 burger and 1 tea cost 4. 2 burgers and 2 cakes cost 9. 1 cake and 2 teas cost 2. What do you have to pay in total for 1 burger, 1 cake and 1 tea? What does each item cost on its own? Explain methods and reasoning.
Solution to Franco s fast food A burger costs 3.50, a cake costs 1 and a tea costs 50p. So the total cost of a burger, a cake and a tea is 5. Explain methods and reasoning.
Coins on the table Anna put some 10p coins on the table. One half of them were tails up. Anna turned over two of the coins, and then one third of them were tails up. How many coins did Anna put on the table? Understand simple fractions. Explain methods and reasoning.
Solution for Coins on the table Anna put 12 coins on the table. Understand simple fractions. Explain methods and reasoning.
A bit fishy A goldfish costs 1.80. An angel fish costs 1.40. Nasreen paid exactly 20 for some fish. How many of each kind did she buy? Solve problems involving ratio and proportion. Choose and use efficient calculation strategies to solve a problem. Explain methods and reasoning.
Solution to A bit fishy Nasreen bought 4 angel fish and 8 goldfish. Solve problems involving ratio and proportion. Choose and use efficient calculation strategies to solve a problem. Explain methods and reasoning.
Anyone for tennis? Two boys and two girls can play tennis. Ali said: I will only play if Holly plays. Holly said: I won t play if Ben is playing. Ben said: I won t play if Luke or Laura plays. Luke said: I will only play if Zoe plays. Zoe said: I don t mind who I play with. Which two boys and which two girls play tennis? Solve a problem by extracting and interpreting data. Explain methods and reasoning.
Solution to Anyone for tennis? Ali, Luke, Holly and Zoe play tennis. Two boys can play. Ben won t play if Luke plays. So the two boys must be Ali and Ben, or Ali and Luke. Ali will play only if Holly plays. Holly won t play with Ben. So the two boys are Ali and Luke. Luke will play only if Zoe plays. So the two girls are Holly and Zoe. Solve a problem by extracting and interpreting data. Explain methods and reasoning.
Join any four numbers. Find their total. Joins can go up, down or sideways, but not diagonally. The score shown is 8 + 15 + 6 + 18 = 47. Find the highest possible score. Joins 8 15 6 9 14 13 18 20 18 17 2 5 3 15 19 6 Find the lowest possible score. Add and subtract two-digit numbers mentally.
Try joining five numbers. Find their total. Joins can go up, down or sideways, but not diagonally. Find the highest possible score. Joins 8 15 6 9 14 13 18 20 18 17 2 5 3 15 19 6 Find the lowest possible score. Add and subtract two-digit numbers mentally.
Try joining five numbers. Now try joining five numbers using only diagonal joins. Find the highest possible score. Find the lowest possible score. Joins 8 15 6 9 14 13 18 20 18 17 2 5 3 15 19 6 Add and subtract two-digit numbers mentally.
Solution to Joins Using four numbers: the highest score is 19 + 15 + 17 + 18 = 69, the lowest score is 6 + 5 + 2 + 17 = 30. Using five numbers: the highest is 20 + 18 + 13 + 17 + 18 = 86, the lowest is 6 + 18 + 2 + 5 + 6 = 37. Using five numbers and diagonal joins: the highest is 19 + 17 + 14 + 15 + 18 = 83, the lowest is 13 + 6 + 20 + 2 + 6 = 47. Add and subtract two-digit numbers mentally.
Money bags Ram divided 15 pennies among four small bags. He could then pay any sum of money from 1p to 15p, without opening any bag. How many pennies did Ram put in each bag? Explain methods and reasoning.
Solution to Money bags Ram put 1p, 2p, 4p and 8p in the four bags. Any sum from 1p to 15p can be made with these amounts. Explain methods and reasoning.
The end,thank you!
References and additional resources. The questions from this PowerPoint came from: Mathematical challenges for able pupils in Key Stages 1 and 2 Corporate writer was Department for Education and Employment and it is produced under a Crown copyright 2000 Thank You PowerPoint template published by www.ksosoft.com These Mental Maths challenges can be found as a PDF file at : http://www.edu.dudley.gov.uk/numeracy/problem_solving/mathematical%20challenges%20book.pdf Contains public sector information licensed under the Open Government Licence v3.0. (http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/) All images used in this PowerPoint was found at the free Public Domain Clip Art site. (https://openclipart.org/) These units were organised using advice given at: http://www.edu.dudley.gov.uk/numeracy/problem_solving/challenges%20and%20blocks.doc